Food allergies are usually manifested by moderate to severe skin rashes, e.g. atopic dermatitis. Patients with food allergies manifested by skin rashes may have severe skin impairment and thus exhibit a constant need for attention. The stratum corneum of the skin, where skin rashes may occur, consists of relatively high levels of ceramides, for example up to as much as 50% of the total lipids in this layer may be comprised of ceramides. These ceramides are present mainly in the extracellular domains (interstices) and are accompanied by nearly equimolar amounts of cholesterol and free fatty acids. The ratio between the ceramides, cholesterol and free fatty acids is believed to be essential for the normal organization of the tissue into the membrane structures that are responsible for proper functioning of the epidermal barrier.
Ceramides are molecules with sphingoid bases connected to a fatty acid via an amide link. Ceramides are structurally heterogeneous and complex group of sphingolipids containing derivaties of sphigosine bases in amide linkage with a variety of fatty acids. Differences in chain length, type and extent of hydroxylation, saturation, etc. are responsible for the heterogeneity of the epidermal sphigolipids. Ceramides may play an essential role in structuring and maintaining the water permeability barrier function of the skin. In conjunction with other corneum lipids, ceramides form ordered structures.
Further, ceramides may be linked to any hexose sugar thus forming hexosyl ceramides. For example, glucosyl-ceramides are present in plant foods and are considered to be very important for skin health. Glucosyl-ceramides are the precursors of gangliosides, which are known to be important for brain development. Dietary gangliosides are known to increase the ganglioside accumulation in brain and other parts of the nervous system as early as age two to four. Gangliosides are available as dietary components only in animal products especially in milk-based products. Gangliosides are part of the milk fat globule membrane, which gets distributed into several milk ingredients during processing.
One of the main solutions for individuals suffering from food allergies is to identify the allergen and avoid it. For example, infants and children with milk and other multiple food protein allergies may be fed hypoallergenic formulas that contain protein hydrolysates sourced from casein, whey, rice, pea, soy, etc. However, given that many nutrients included in pediatric nutritional compositions, including infant formulas, include ingredients sourced from animal sources, these additional ingredients may inadvertently introduce allergens to the nutritional composition.
For example, gangliosides cannot be added to many hypoallergenic products, unless highly purified, due to the risk of cross-contamination with milk proteins. It is believed that the human body is capable of producing gangliosides provided the precursors are available to the body in dietary form. However, synthesis of several types of gangliosides as required by the body may be limited by the presence of galactose and sialic acid in the system.
Accordingly, it would be beneficial to provide nutritional composition that includes ceramides that may alleviate skin issues, including skin rashes. Further, it is beneficial to provide a nutritional composition including ceramides derived from a plant-based source so as not to introduce allergens in the nutritional composition. Moreover, providing a nutritional composition that includes cermides may promote brain and eye health and/or development in individuals suffering from certain food allergies, especially children and infants.
Moreover, disclosed herein are methods for reducing the severity of a food allergy manifesting as a skin condition or promoting brain development in a subject by administering a hypoallergenic nutritional composition including ceramides derived from a plant-based source.